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-   -   GTM Stage 1.5 supercharger build (http://www.the370z.com/forced-induction/76279-gtm-stage-1-5-supercharger-build.html)

Baer383 09-17-2013 04:22 PM

You won't have to mess with the "K" factor at all just get the tune from Sam and start with that ,Sam's tunes are good you just have to lean them out.

pokeyl 09-17-2013 07:22 PM

Quote:

Originally Posted by Baer383 (Post 2492306)
You won't have to mess with the "K" factor at all just get the tune from Sam and start with that ,Sam's tunes are good you just have to lean them out.


I only changed the K Factor because I ran the large injectors for a week before I did the supercharger install.

pokeyl 09-17-2013 07:28 PM

Quote:

Originally Posted by snowsurfdirtx (Post 2492295)
Baer: Thanks, I will keep that in mind, I really appreciate it.

pokeyl: Good to know, thanks man. How long did the 3rd weekend take? I'm guessing with the cable, I can change the "K Factor" with my laptop? I'd love to learn how to tune myself.

I have my Jeep for DD duties while she's down. Gonna try and install gauges next week maybe. I gotta order those sometime this week. Where did you guys tap in for your boost gauge?

Week 3 was two 8 hour days, that was taking my time and checking it twice, The instructions are "spot on"!!!

I had a used kit, a new one with all the parts should go faster.

pokeyl 09-17-2013 07:32 PM

Maps
If someone can tell me the stock crankshaft pulley size I'll do the math on the two at 3000-7500 at different boost/SC pulley sizes.

http://www.the370z.com/members/pokey...644-c38-81.jpg

http://www.the370z.com/members/pokey...645-c38-91.jpg

snowsurfdirtx 09-17-2013 08:59 PM

Awesome, thanks.

And I'll try and get you those numbers. Interested in seeing what it is

pokeyl 09-18-2013 09:15 AM

This is the best "One Stop" I have found. He keeps the math easy and runs all the variables.


reading a compressor map :: motorgeek.com

Now you’ll notice on the vertical side of the chart is the pressure ratio and then the bottom horizontal line of the chart is the air flow in either LB/min or some display CFM (cubic feet per minute). To convert Lbs/min into CFM you need to consider the temperature of the air. Most compressor maps are taken at 85 degrees Fahrenheit. You can normally tell from the formulas written on the map which will have the number 545 and by subtracting 460 from that number you convert it to Fahrenheit. One cubic foot of air at 85F weighs 0.07282 pounds. So, at 85F, convert pounds per minute to CFM by multiplying by 13.73. This will come in handy in a little while.

To start off reading the compressor map first decide your boost goal. Say you want to run 15 psi on this T04E 40 trim map. You need to find the pressure ratio which is the absolute pressure at the outlet of the turbo. To find the pressure ratio add the boost you want to run (15 psi) to atmospheric pressure (14.7 unless you are at altitude which you can adjust to your numbers accordingly) and then divide by atmospheric pressure. So it looks like:

Pressure Ratio = (15 + 14.7) / 14.7 = 2.02

So if you draw a line horizontally across the compressor map just barely above the number 2 on the pressure ratio side of the map you can see it cuts through the middle of the map. Now if you look at the range from the surge line to the end of the balloon, we have a range from 15 lbs/min to 35lbs/min. Which now if you wanted to convert into CFM by multiplying by 13.73 like earlier mentioned you get a range from 205 CFM to 480 CFM.

So this all sounds pretty sweet , but we need to consider that the engine at a given intake pressure will only be able to ingest so much air. To figure out how much air flow you’ll have in your engine you need to start with the displacement of your engine and an RPM point.

CFM for 4 stroke = Displacement in CI / 3456 * RPM * VE

VE is volumetric efficiency, which is a value indicating how much of the potential air flow volume actually makes it through the engine at a given RPM. Now most of the time unless you know the VE you’ll be guessing, but if you take the hp you know you have on some online engine calculators you can work backwards and adjust the VE number until the HP numbers match up. For this write up I’ll just throw numbers in there. So a stock MC engine is 2226CC or about 136 cu in and at 6000 rpm and 90 percent VE ( .90) it will flow:

136 / 3456 * 6000 * .9 = 212.5 CFM

Now some people might be thinking that this would put you in a good spot between the flow range that was figured out earlier, but the 212.5 CFM is only tell you what the engine will flow if naturally aspirated. So that being said if you do this math for a different engine or a different map and it doesn’t land in that range and looks like it’s in the surge or choke range don’t worry about it too much just yet. To determine what it will do under boost, you have to determine what density ratio of the compressor and intercooling system will give you. To do that we need to take our boost point and determine how hot the compressor is going to make the air at a that boost:

Tout (in F) = (((Tin (in F) + 460) * (Pressure Ratio0.283)) - 460)

For 15psi of boost at sea level at an ambient temp of 85F (85F in this case so that our computed CFM ends up matching that of the compressor map).

Tout = (85 + 460) * 2.020^.283 - 460 = 205F

This assumes an ideal, 100% efficient compressor. The round circles in the compressor map tell us how efficient the compressor is going to be at a given pressure ratio and flow level. Since most of the map is at least 70% (.70) efficient or better (adjust this number for what range you're shooting for), we'll use that figure and double check later to make sure we were either close or underestimating a little. Our real outlet temperature is going to be:

delta T actual = delta T ideal / efficiency

For our example, the delta T ideal is 205F - 85F or 120F:

delta T actual = 120F / 0.70 = 171F

171F is how much the compressor is going to heat the air above the inlet temp, so the real outlet temp is 171 + 85, or 256F. What happens when this air mass hits the intercooler? Two things: first, a pressure drop and second, a temperature drop. The pressure drop is going to be about .5 psi for a smaller intercooler or something like a side mount. Lets assume a 65% efficiency from the smaller intercooler which isn’t the best, but I’ve seen a lot of people pushing things harder then that and a lot of people way better off then that. To figure out the intercooler efficiency and the pressure drop you would use: (IC = intercooler)

T IC drop = (T IC in - T ambient) * IC efficiency

T IC drop = (256 - 85) * 0.65 = 111F

The IC will drop the turbo outlet temp by 111F, turning the 256F air into 145F air and dropping the pressure 0.5psi to 14.5psig. To figure out what this would do to the naturally aspirated engine we have to figure out the density ratio

Density ratio= ((Tin + 460) / (Tout + 460)) * (Pout / Pin)

Density ratio = ((85+460)/(145+460))*(14.5+14.7)/14.7 = 1.79

This density ratio means that you will get 1.79 times as much air flowing through the engine with this compressor and intercooler combination at this pressure point and this ambient temperature than you would in normally aspirated mode. Going back to our 212.5 CFM value, we multiply that by the density ratio to get 380.1 CFM which converts to 27.7 Lbs/min

With all this information you can now draw a line vertical from the 27.7 Lbs/min area on the bottom line of the compressor map and cross through the original horizontal line from the pressure ratio we see that with the MC engine and this 40 trim wheel at 6000 rpm with the intercooler setup we used you can see we’re on the edge of 73 percent efficiency. Now with all the numbers we guessed on like the VE and the intercooler efficiency and if the ambient temperature was different in real life then from the map things could change for the better or worse so this is really like I said before just to give you an idea.

What makes it a little tough to predict what you really are going to get is getting an idea of what the final VE of the system will be (which is not constant, but changes across the RPM/Manifold pressure range) since the turbine housing and wheel themselves are going to have an effect on the VE map. You can have a turbo too small that actually takes VE away from the engine after a certain RPM and can cause choking.

Since we have the numbers calculated we should see whether the compressor will be forced into the surge line. Surge is caused when the engine cannot ingest enough air to keep the compressor inside its map. We saw that at a 2.02 pressure ratio, the surge line is around 15 pounds per minute or 205 CFM. Now, let's assume that the turbine and turbine housing we will choose can power the compressor to reach 15psi by 3500RPMs. We keep the density ratio the same, but we have to re-compute the flow for the engine at 3500RPMs. The VE at this point should be better than at 6000, so we'll use another guessed value of 95%. At 3500RPMs, the engine will be ingesting:

CFM = 136 / 3456 * 3500 * 0.95 = 130.8 CFM

That's in normally aspirated mode. Multiplying the density ratio, we get:

130.8 CFM * 1.79 = 234.1 CFM

This isn’t near the surge limit, but if it were you can fix most of these problems by switching the turbine housing with a larger A/R (aspect ratio). By doing that you’ll slow down the spool up time to bring the compressor up to this pressure ratio when the engine is revving a little faster and ingesting more air.

With all that was guessed during this there is a definite fudge factor so there might still be some trial and error, but at least this will give you a better idea of where you should be with your goals. For all of you reading this I hope it comes out clear I think I pulled my brain into a knot. I’m not a math wiz so if I’d made any mistakes or you see anything not said right just tell me…we all make mistakes. :-)

Baer383 09-18-2013 09:27 AM

I got a Fvcking headache looking at that,stop that Sh!t

ANMVQ 09-18-2013 09:38 AM

POKEYL great write up man, but agree with Baer383, HEADACH.. LOL

snowsurfdirtx 09-18-2013 10:38 PM

my buddy sent me this today:

"Steveo, the only way to find out whether to run the cats or not is on a chassis dyno. you need to try it both ways. A lot of cam grinders run big over lap on boosted cars. For example on a vw, most all of the good performance cam grinders use 108 degree lobe centers, but with turbos they run an asymmetrical grind and 110 degree lobe centers. Some chevy cam grinders, like Crane use 114 degree lobe centers for supercharged motors, then guys like comp cams...they use 110 degree lobe centers, so with out a dyno it’s any body's guess. Tim"

Does anyone have info on our cams that I can send him? Maybe a link to some hard info about our cams, how vvel works exactly, etc? He's like a father to me, and knows his stuff and wants to help as much as he can. He's built some pretty amazing motors.

pokeyl 09-19-2013 07:44 AM

NO more math just results
This is at 7500 RPM with a 146mm crank (stock) pulley.



http://www.the370z.com/members/pokey...6-sc-speed.jpg

theDreamer 09-19-2013 07:47 AM

For some info on VVEL:
http://www.youtube.com/watch?v=6i1rBkP8dYs

Baer383 09-19-2013 07:52 AM

Quote:

Originally Posted by pokeyl (Post 2495225)
NO more math just results
This is at 7500 RPM with a 146mm crank (stock) pulley.



http://www.the370z.com/members/pokey...5-sc-speed.jpg


Thanks!!!

SS_Firehawk 09-19-2013 10:25 AM

Quote:

Originally Posted by snowsurfdirtx (Post 2494825)
my buddy sent me this today:

"Steveo, the only way to find out whether to run the cats or not is on a chassis dyno. you need to try it both ways. A lot of cam grinders run big over lap on boosted cars. For example on a vw, most all of the good performance cam grinders use 108 degree lobe centers, but with turbos they run an asymmetrical grind and 110 degree lobe centers. Some chevy cam grinders, like Crane use 114 degree lobe centers for supercharged motors, then guys like comp cams...they use 110 degree lobe centers, so with out a dyno it’s any body's guess. Tim"

Does anyone have info on our cams that I can send him? Maybe a link to some hard info about our cams, how vvel works exactly, etc? He's like a father to me, and knows his stuff and wants to help as much as he can. He's built some pretty amazing motors.

I'm not running stock cats, but I have one in my MD Y pipe and a more restrictive exhaust compared to an X or H design. It's a 200cell 3". I also have a resonator too. Ill be posting more results when I get her home and strapped in.

snowsurfdirtx 09-22-2013 09:33 PM

Sounds good man. I bet that you need that little bit with your PPE's. In for results!

snowsurfdirtx 09-23-2013 07:22 AM

Hey guys,

Can I use a thermostatic sandwich plate from an old oil cooler setup here or do I need GTM's inline thermostat due to the way the filter is relocated? (it seems insanely expensive for the GTM line kit since I think it's just a Mocal thermostat)

Baer383 09-23-2013 07:34 AM

Quote:

Originally Posted by snowsurfdirtx (Post 2500277)
Hey guys,

Can I use a thermostatic sandwich plate from an old oil cooler setup here or do I need GTM's inline thermostat due to the way the filter is relocated? (it seems insanely expensive for the GTM line kit since I think it's just a Mocal thermostat)

You can but Sam has all the lines and everything pre made.

Z eliminator 09-23-2013 07:50 AM

Great info on the SC. so what happens when you and meth in the intercoller and injected into all six intake ports. The charge cools down ?
how will the numbers change /

thanks

Z

SS_Firehawk 09-23-2013 08:39 AM

I have direct port meth injection installed. It only sprays when I start boosting pretty hard (over 5500rpm) I'm really using it to cool the IAT's. LTH's really warm things up, especially with all the other things stuffed under the hood. I'm sure it's good for 20-40whp, but honestly, the damn car is so flipping fast, I won't be able to tell if it did.

snowsurfdirtx 09-23-2013 01:06 PM

Quote:

Originally Posted by Baer383 (Post 2500288)
You can but Sam has all the lines and everything pre made.

Yeah, they quoted me for the lines + inline thermostat.. 455. Seemed steep for just some lines, fittings and a mocal thermostat. Figured.. use the sandwich plate and their line kit w/o thermostat, if I can, but I'm not sure how the line setup is to begin with. Looks like I'd have to cap some fittings? Can't tell. Might just give up and order it all thru gtm.

Baer383 09-23-2013 02:33 PM

Look thru my albums I may have some pics there,if not pm me and I may have some on my lap top.:tiphat:

SPOHN 09-23-2013 02:56 PM

Quote:

Originally Posted by Baer383 (Post 2501353)
Look thru my albums I may have some pics there,if not pm me and I may have some on my lap top.:tiphat:

All I see is midget porn

pokeyl 09-24-2013 06:54 PM

My oil cooler solution, this is the long filter. I will be going back to the standard hight one! It will not stick out below the frame.

http://i115.photobucket.com/albums/n...psef8b08cb.jpg

http://i115.photobucket.com/albums/n...psfb5cc92d.jpg

fuct 09-25-2013 08:47 AM

is the zip tie doing anything in the pic above? are you worried the hose will pull off right there?

SPOHN 09-25-2013 10:52 AM

Socket less fittings, me no trust.

snowsurfdirtx 09-25-2013 12:21 PM

I agree SPOHN. Doesn't oil press hit almost 100lbs on cold startup? I'd throw some clamps on there. Is that filter relocated or just has a sandwich plate on there?

Baer, I'll check em out today man and I'll let ya know

fuct 09-25-2013 12:54 PM

ahh gotcha

1slow370 09-25-2013 01:39 PM

you could try fuel injection clamps but whatever you use don't go too tight or you can cut into the inner hose with the barb. the fuel injection ones are less damaging to the outside of the hose than the worm style. I usually just opt for crimped fittings and take them to a napa.

pokeyl 09-25-2013 02:08 PM

LINK
http://www.the370z.com/diy-section-d...ttsa-pics.html

pokeyl 09-25-2013 02:09 PM

Quote:

Originally Posted by snowsurfdirtx (Post 2504420)
I agree SPOHN. Doesn't oil press hit almost 100lbs on cold startup? I'd throw some clamps on there. Is that filter relocated or just has a sandwich plate on there?

Baer, I'll check em out today man and I'll let ya know


Is that filter relocated or just has a sandwich plate on there?

Yes! and Yes!

snowsurfdirtx 09-27-2013 07:20 AM

Awesome! Thanks pokeyl.

Update: after talking to Aeroforce, I decided to go with their Interceptor gauge which is a combo OBD-2 and analog input gauge(2 inputs) for my wideband AFR and oil pressure gauge. Still debating where to mount the suckers :/ I saw a guy mount one to the right of his clock.. real low.. with a clean holder. Might velcro one there and see how it looks.

snowsurfdirtx 10-16-2013 11:56 AM

1 Attachment(s)
so.. I'm trying to picture how the oil cooler is going to get tied in. Please ignore my awesome paint skills lol

From what I hear, the relocation adapter should oil to the inline thermostat, which then goes to the oil cooler, which then goes back through the thermostat to the relocated oil filter and then back to the engine. Does this sound about right? Trying to get my lines figured out

snowsurfdirtx 11-05-2013 10:55 AM

just a little update: there were some production issues and stuff going on at GTM so still waiting on the kit to be completed. once the intakes are finished hopefully this week or next the kit should be on the way to my house.

Voice59 11-05-2013 12:01 PM

Quote:

Originally Posted by snowsurfdirtx (Post 2556111)
just a little update: there were some production issues and stuff going on at GTM so still waiting on the kit to be completed. once the intakes are finished hopefully this week or next the kit should be on the way to my house.

Likewise...hopefully.

snowsurfdirtx 01-22-2014 03:13 AM

So, another update. I drove down to California, and picked up my kit directly from Sam@GTM.. and what a sweet shop, btw. My Bosche injectors are backordered, but Sam said he'd send them out ASAP when they arrive. I have yet to unbox and take pictures since I got in this past weekend and went straight back to work. So once everything is in hand, I'll be starting my build. Still need a couple of random things for my supporting mods, nothing major though. Finally, it's alllll coming together.

Voice59 01-22-2014 10:54 AM

I'm still waiting on mine... :(

snowsurfdirtx 01-24-2014 02:35 AM

Quote:

Originally Posted by Voice59 (Post 2662108)
I'm still waiting on mine... :(

What parts are you waiting on still? Did they say? There were probably 10+ boxes same size as mine all lined up in various stages of work. Sam is a nice guy, knows his stuff and I was impressed with the quality there.. I just think they need a few more workers is all for the amount of work they have. I even offered when I get out of the military to go work there :icon17:

Voice59 01-26-2014 01:15 AM

He said fuel injectors and a "few" other things. He said worst case scenario it'll be shipped out the end of this coming week I think. Either that or last week.

Ill 01-26-2014 01:55 AM

Hopefully they will be sent soon.

I am still waiting on my back order ECU reflash cable for my turn key TT kit. They were going to be back in stock "within a day or two", according to an employee, about two weeks ago. As of yesterday they "have been in stock for awhile", from another employee.

I guess only time will tell.

Voice59 01-31-2014 07:06 PM

Yeah just got told my order would get shipped out worst case scenario ANOTHER 2 weeks after worst case scenario being the end of this week.

snowsurfdirtx 02-01-2014 09:49 AM

1 Attachment(s)
:tup: woohoo!

hopefully you get yours soon man. i need to call Sam about my injectors and stuff monday. lemme know when he confirms hes sending it out


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